Observation of Videos
I hate making observations of event such as this, however if you view the first link I posted in full screen slowly you will observe at time 02 seconds a puff of what looks like smoke when the A/C is just left of centre of the rotor head. Additionally there seems to be other events at time 04 seconds, 05 seconds and 06 seconds.
I hope that somebody can on pass this comment to the Royal Thai Airforce.
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